1. You can set your camera to have more saturation. On a Canon, select Menu, scroll through to Picture Style , select User defined and move down to saturation settings. At some point you need to press Q or info in order to edit that setting. Put it up by one or two points. I’m not sure how to do this with a Nikon, but your manual will tell you.
2. If you have some green to expose on, do that and refocus on the subject you are taking. Forget that it is no longer in the centre of your exposure setting. Take the shot.
I must say that I forget to expose on green quite often, but I have my camera set to vivid all the time.
Here is a photo with no editing done to it which I took with a 2+ setting on saturation in a user defined picture style